Peroneal Tendon Subluxation – When Your Tendon Slips Out of Place

Peroneal Tendon Subluxation – When Your Tendon Slips Out of Place You feel a sudden "pop" or snapping sensation on the outside of your ankle. Your ankle feels unstable, and you notice a bump or bulge on the outer ankle that seems to slide in and out of place. These symptoms suggest peroneal tendon subluxation—a condition where the tendons supporting your ankle slip out of their normal groove. If you're experiencing these symptoms in Central Florida, understanding this condition is your first step toward relief and preventing long term damage. What Are the Peroneal Tendons? The peroneal tendons are two strong tissues that run along the outside of your ankle: Peroneus longus —helps turn your foot outward and stabilizes your ankle Peroneus brevis —assists with outward foot rotation and ankle stability These tendons normally sit snugly in a bony groove called the peroneal groove on the outer side of your ankle, held in place by a strong ligament. When subluxation occurs, the tendons slip out of this groove—sometimes partially, sometimes completely—causing pain, instability, and that characteristic "popping" sensation. Causes: How the Tendon Slips Out Peroneal tendon subluxation develops through several mechanisms: Acute Injury Ankle sprain —forcing your foot inward violently, damaging the retaining ligament Direct trauma —a blow to the outside of the ankle Sudden directional change —rapidly rotating your foot while running or playing sports Structural Factors Shallow peroneal groove —a anatomical variation that naturally reduces retaining grip Loose retaining ligament —weakened tissue that fails to hold tendons securely Repetitive stress —high impact activities gradually stretching the supporting structures Chronic Causes Chronic ankle instability —from previous sprains that damaged stabilizing structures Intense athletic activity —particularly in football, basketball, and track and field Improper footwear —shoes that don't provide adequate ankle support Athletes and active individuals in the Orlando, Altamonte Springs, Longwood, Lake Mary, and Sanford areas frequently experience this injury. Symptoms: When Your Tendon Feels Like It's Sliding If you have peroneal tendon subluxation, you'll likely notice: "Popping" or "snapping" sensation —especially with certain movements or ankle positions Lateral ankle pain —on the outside of your ankle Swelling on the outer ankle —often localized to the peroneal groove area Visible bulge or bump —that seems to move when you move your foot Ankle instability —feeling like your ankle might give way Difficulty with athletic activities —particularly sports requiring quick directional changes Pain with specific movements —especially when rotating your foot outward Symptoms may come and go depending on activity level and ankle positioning. Some people experience constant discomfort, while others notice symptoms primarily during sports or high impact activities. Diagnosis: Seeing the Subluxation Accurate diagnosis requires both physical examination and imaging. At CFFAI's locations throughout Central Florida, Dr. Sean Griffin uses a comprehensive diagnostic approach: Physical Examination We reproduce the subluxation by positioning your ankle in specific ways that make the tendons slip, confirming the diagnosis and assessing severity. Imaging Studies Ultrasound —dynamic imaging that shows the tendon's position during movement, perfectly visualizing subluxation MRI —detailed images of tendon position, retaining ligament integrity, and associated soft tissue damage X rays —rule out associated fractures of the peroneal groove or ankle bones Ultrasound during ankle movement (dynamic ultrasound) is particularly effective for confirming peroneal tendon subluxation. Treatment Options: From Bracing to Surgical Repair Conservative Management (Initial Treatment) For partial subluxation or acute cases, conservative care is the first approach: Immobilization —boot or splint keeping your ankle in stable position for 2–6 weeks Anti inflammatory medications —NSAIDs to reduce pain and swelling Rest from aggravating activities —avoiding sports and high impact movement while healing Physical therapy —strengthening ankle stabilizers and proprioceptive training Proper bracing —after initial healing, specialized ankle braces prevent re subluxation during activity Many patients with mild cases maintain stability with conservative care and bracing. Surgical Repair When conservative treatment fails or subluxation is severe and complete: Retaining ligament repair or reconstruction —tightening or replacing the ligament holding tendons in place Peroneal groove deepening —increasing the groove's depth to better grip tendons Tendon relocation —repositioning tendons if necessary Surgical outcomes are excellent, particularly when performed by experienced surgeons like Dr. Sean Griffin. Recovery involves gradual rehabilitation over 3–6 months. When to See a Podiatrist If you experience the snapping, popping, or uns